滇池不同湖区沉积物正构烷烃的分布特征及其环境意义  

Distribution Characteristics of n-alkanes in Sediment Core and Implication of Environment in Different Lakes of Dianchi

作　　者：余丽燕[1] 韩秀秀[1] 黄晓虎[1] 吴亚林[1] 杨浩[1] 黄涛[1] 余艳红[2] 黄昌春[1,3] 

机构地区：[1]南京师范大学地理科学学院,南京210023 [2]云南省环境科学研究院,昆明650032 [3]江苏省地理信息资源开发与利用协同创新中心,南京210023

出　　处：《环境科学》2016年第12期4605-4614,共10页Environmental Science

基　　金：国家自然科学基金青年科学基金项目(41503075);国家自然科学基金项目(41571324;41673108);中国博士后科学基金项目(2015M581826);云南省环境科学研究院(中国昆明高原湖泊国际研究中心)开放基金项目

摘　　要：为探明滇池沉积物中有机质的组成特征及其环境意义,2014年7月采集滇池北部和南部各一根柱状沉积物样品,分析了TOC(总有机碳)、TN(总氮)、正构烷烃含量剖面变化规律.结果表明:1滇池沉积物中TOC与TN自20世纪70年代以后增加显著,说明了滇池初级生产力不断提高;2滇池沉积物正构烷烃代用指标n-C27/n-C31比值及Paq和CPI表明,滇池沉积物从下往上草本植物与木本植物交替变化,且沉积物中的高碳数有机质主要来自滇池内源的沉水和漂浮大型植物;3C/N比值及正构烷烃分布特征表明,滇池不同湖区沉积物有机质来源存在差异:滇池北部沉积物中有机质主要来源于內源植物和陆源有机物的人为源;滇池南部沉积物中有机质主要来源于內源大型水生植物和陆源高等植物混源.为此,在今后滇池沉积物有机质的研究中,应加强对滇池不同湖区有机质的深入分析.In order to study the composition and environment significance of the organic matter in Lake Dianchi,samples from two sediment cores from the northern and southern parts of the lake were collected in July,2014. Meanwhile,the vertical distributions of total organiccarbon（ TOC）,total nitrogen（ TN）,n-alkanes fractions were investigated. The results showed that 1 the concentrations of TOC and TN had been clearly increasing since the 1970 s,which implied that the primary productivity of Lake Dianchi was continuously enhanced; 2 The values of the parameter n-C27/ n-C31,Paqand CPI indicated the alternation between herbs and woody plants from the bottom up in Lake Dianchi sediments. Besides,the high carbon number of organic matter in sediments mainly originated from endogenous submerged floating and large plants; 3 The index of C / N and distribution characteristics of n-alkanes suggested differences in the various sources of organic matter in different lakes. In detail,organic matter came from terrigenous organic matter of anthropogenic sources and endogenous bacteria in the sediments of northern Dianchi,while organic matter was derived from endogenous aquatic and terrestrial higher plants mixed source in the sediments of southern Dianchi. Finally,it is worthwhile to emphasize further research on organic matter in different lakes of Lake Dianchi.

关 键 词：滇池 正构烷烃 不同湖区 

分 类 号：X524[环境科学与工程—环境工程]